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1.
Cell Death Discov ; 10(1): 404, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39285178

RESUMO

Radiotherapy (RT) is a crucial treatment for colorectal cancer (CRC) patients, but it often fails to induce systemic antitumor immunity. CD73, an immunomodulatory factor, is upregulated after RT and associated with poor prognosis in CRC patients. This study aims to elucidate the mechanisms driving RT-induced CD73 upregulation in CRC and investigate how combining RT with CD73 blockade stimulates immune responses and induces abscopal effects. Findings revealed that RT-induced CD73 upregulation is mediated by the ataxia telangiectasia and Rad3-related (ATR) pathway and correlated with RT tolerance, as demonstrated through flow cytometry, immunofluorescence, and Western Blotting. Using flow cytometry and multicolor immunofluorescence, experiments demonstrated that in CRC subcutaneous tumor models, combination therapy reduces the infiltration of myeloid-derived suppressor cells (MDSCs), tumor-associated macrophages (TAMs), and regulatory T cells (Tregs) while increasing dendritic cells (DCs) and CD8 + T cells, resulting in superior antitumor responses. Additionally, results from flow cytometry, Western Blot, and RNA sequencing demonstrated that combination therapy enhances the antigen-presenting ability of DCs and activates tumor antigen-specific CD8 + T cells, improving their function and delaying their depletion. The activation of the cGAS-STING and IFN-I pathways is crucial for this effect. In summary, the integration of RT with CD73 blockade effectively reverses the immunosuppressive TME and invigorates CD8 + T cell-driven, specific antitumor immune responses. These insights shed fresh light on the mechanisms governing the synergistic modulation of immunity by RT and CD73 blockade in CRC, offering promising avenues for the advancement of therapeutic strategies against CRC.

2.
Radiat Oncol ; 19(1): 88, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38978062

RESUMO

PURPOSE: This study aimed to develop an automated Tomotherapy (TOMO) planning method for cervical cancer treatment, and to validate its feasibility and effectiveness. MATERIALS AND METHODS: The study enrolled 30 cervical cancer patients treated with TOMO at our center. Utilizing scripting and Python environment within the RayStation (RaySearch Labs, Sweden) treatment planning system (TPS), we developed automated planning methods for TOMO and volumetric modulated arc therapy (VMAT) techniques. The clinical manual TOMO (M-TOMO) plans for the 30 patients were re-optimized using automated planning scripts for both TOMO and VMAT, creating automated TOMO (A-TOMO) and automated VMAT (A-VMAT) plans. We compared A-TOMO with M-TOMO and A-VMAT plans. The primary evaluated relevant dosimetric parameters and treatment plan efficiency were assessed using the two-sided Wilcoxon signed-rank test for statistical analysis, with a P-value < 0.05 indicating statistical significance. RESULTS: A-TOMO plans maintained similar target dose uniformity compared to M-TOMO plans, with improvements in target conformity and faster dose drop-off outside the target, and demonstrated significant statistical differences (P+ < 0.01). A-TOMO plans also significantly outperformed M-TOMO plans in reducing V50Gy, V40Gy and Dmean for the bladder and rectum, as well as Dmean for the bowel bag, femoral heads, and kidneys (all P+ < 0.05). Additionally, A-TOMO plans demonstrated better consistency in plan quality. Furthermore, the quality of A-TOMO plans was comparable to or superior than A-VMAT plans. In terms of efficiency, A-TOMO significantly reduced the time required for treatment planning to approximately 20 min. CONCLUSION: We have successfully developed an A-TOMO planning method for cervical cancer. Compared to M-TOMO plans, A-TOMO plans improved target conformity and reduced radiation dose to OARs. Additionally, the quality of A-TOMO plans was on par with or surpasses that of A-VMAT plans. The A-TOMO planning method significantly improved the efficiency of treatment planning.


Assuntos
Órgãos em Risco , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Neoplasias do Colo do Útero , Humanos , Neoplasias do Colo do Útero/radioterapia , Feminino , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Órgãos em Risco/efeitos da radiação
3.
Adv Mater ; 36(19): e2304991, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38408365

RESUMO

The eradication of osteomyelitis caused by methicillin-resistant Staphylococcus aureus (MRSA) poses a significant challenge due to its development of biofilm-induced antibiotic resistance and impaired innate immunity, which often leads to frequent surgical failure. Here, the design, synthesis, and performance of X-ray-activated polymer-reinforced nanotherapeutics that modulate the immunological properties of infectious microenvironments to enhance chemoradiotherapy against multidrug-resistant bacterial deep-tissue infections are reported. Upon X-ray radiation, the proposed polymer-reinforced nanotherapeutic generates reactive oxygen species and reactive nitrogen species. To robustly eradicate MRSA biofilms at deep infection sites, these species can specifically bind to MRSA and penetrate biofilms for enhanced chemoradiotherapy treatment. X-ray-activated nanotherapeutics modulate the innate immunity of macrophages to prevent the recurrence of osteomyelitis. The remarkable anti-infection effects of these nanotherapeutics are validated using a rat osteomyelitis model. This study demonstrates the significant potential of a synergistic chemoradiotherapy and immunotherapy method for treating MRSA biofilm-infected osteomyelitis.


Assuntos
Biofilmes , Staphylococcus aureus Resistente à Meticilina , Osteomielite , Polímeros , Infecções Estafilocócicas , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/fisiologia , Osteomielite/tratamento farmacológico , Osteomielite/terapia , Osteomielite/microbiologia , Animais , Infecções Estafilocócicas/tratamento farmacológico , Biofilmes/efeitos dos fármacos , Ratos , Polímeros/química , Polímeros/farmacologia , Quimiorradioterapia/métodos , Antibacterianos/farmacologia , Antibacterianos/química , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Nanopartículas/química , Espécies Reativas de Nitrogênio/metabolismo
4.
Int J Biol Macromol ; 253(Pt 8): 127568, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37866582

RESUMO

Aquaporin 4 (AQP4) facilitates the transport of reactive oxygen species (ROS). Both cancer cells and the ionizing radiation microenvironment can induce posttranslational modifications (PTMs) in AQP4, which may affect its permeability to ROS. Because this ROS diffusion process is rapid, microscopic, and instantaneous within and outside cells, conventional experimental methods are inadequate for elucidating the molecular mechanisms involved. In this study, computational methods were employed to investigate the permeability of exogenous ROS mediated by radiation in AQP4 at a molecular scale. We constructed a simulation system incorporating AQP4 and AQP4-Cysp13 in a complex lipid environment with ROS. Long-timescale molecular dynamics simulations were conducted to assess the structural stability of both AQP4 and AQP4-Cysp13. Free energy calculations were utilized to determine the ROS transport capability of the two AQP4 proteins. Computational electrophysiology and channel structural analysis quantitatively evaluated changes in ROS transport capacity under various radiation-induced transmembrane voltage microenvironments. Our findings demonstrate the distinct transport capabilities of AQP4 channels for water molecules and various types of ROS and reveal a decrease in transport efficiency when AQP4 undergoes palmitoylation modification. In addition, we have simulated the radiation-induced alteration of cell membrane voltage, which significantly affected the ROS transport capacity. We propose that this research will enhance the understanding of the molecular mechanisms governing the transport of exogenous ROS by AQP4 and elucidate the influence of palmitoylation on ROS transport. This study will also help clarify how different structural features of AQP4 affect the transport of exogenous ROS mediated by radiotherapy, thereby providing a theoretical molecular basis for the development of new treatment strategies that combine with radiotherapy.


Assuntos
Aquaporina 4 , Lipoilação , Aquaporina 4/química , Aquaporina 4/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Membrana Celular/metabolismo , Permeabilidade , Água/metabolismo
5.
Cell Rep Med ; 4(8): 101151, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37567173

RESUMO

Although radiotherapy (RT) has achieved great success in the treatment of non-small cell lung cancer (NSCLC), local relapses still occur and abscopal effects are rarely seen even when it is combined with immune checkpoint blockers (ICBs). Here, we characterize the dynamic changes of tumor-infiltrating immune cells after RT in a therapy-resistant murine tumor model using single-cell transcriptomes and T cell receptor sequencing. At the early stage, the innate and adaptive immune systems are activated. At the late stage, however, the tumor immune microenvironment (TIME) shifts into immunosuppressive properties. Our study reveals that inhibition of CD39 combined with RT preferentially decreases the percentage of exhausted CD8+ T cells. Moreover, we find that the combination of V-domain immunoglobulin suppressor of T cell activation (VISTA) blockade and RT synergistically reduces immunosuppressive myeloid cells. Clinically, high VISTA expression is associated with poor prognosis in patients with NSCLC. Altogether, our data provide deep insight into acquired resistance to RT from an immune perspective and present rational combination strategies.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Animais , Camundongos , Linfócitos T CD8-Positivos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/metabolismo , Recidiva Local de Neoplasia/metabolismo , Células Mieloides , Microambiente Tumoral
6.
Cell Death Discov ; 9(1): 180, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37291116

RESUMO

High-dose hypofractionated radiotherapy (HRT) is an important anticancer treatment modality that activates antitumor host immune responses. However, HRT for oligometastases of colorectal cancer (CRC) has shown frustrating results in the clinic. As part of immune evasion, myeloid cells express signal regulatory protein α (SIRPα) to inhibit phagocytosis by phagocytes in the tumor microenvironment (TME). We postulated that SIRPα blockade enhances HRT by alleviating the inhibitory action of SIRPα on phagocytes. We demonstrated that SIRPα on myeloid cells was upregulated in the TME after HRT. When SIRPα blockade was administered with HRT, we observed superior antitumor responses compared with anti-SIRPα or HRT alone. When anti-SIRPα was administered to local HRT, the TME could become a tumoricidal niche that was heavily infiltrated by activated CD8+ T cells, but with limited myeloid-derived suppressor cells and tumor-associated macrophages. While CD8+ T cells were required for the effectiveness of the anti-SIRPα + HRT combination. The triple therapy with anti-SIRPα + HRT + anti-PD-1 had superior antitumor responses compared with the combination of any two therapies and established a strong and long-lasting adaptive immunological memory. Collectively, SIRPα blockade provides a novel way to overcome HRT resistance in oligometastatic CRC patients. Our results herein provide a valuable cancer treatment strategy that has the potential to be translated into clinical practice.

7.
Int J Biol Macromol ; 224: 766-775, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36283546

RESUMO

Protein-lipid interactions are an essential element of the function of many membrane ion-channel proteins. These potential interactions should be considered alongside the diversity and complexity of membrane lipid composition. Phospholamban (PLN) is an inhibitor of sarcoplasmic reticulum Ca2+ ATPase (SERCA). PLN is a 52-residue transmembrane protein encoded by lncRNA, and PLN monomers form stable pentamers of biological function in a lipid bilayer membrane. Some earlier studies suggest that it can form a cationic selective channel, while others suggest that it can only store ions. Here, we report the distribution of different lipids in the membrane and the structural dynamics and conductance properties of PLN pentamers after coarse-grained (CG) and all-atom (AA) molecular dynamics simulations of different systems. The results show that cholesterol is highly enriched around the protein and stabilizes the structure of the PLN pentamer. The absence of cholesterol increases the flexibility of the protein backbone. The conductance properties of monovalent ions and water suggest that they cannot spontaneously permeate through the PLN pentamer channel pore. However, the energy barrier to overcome is much lower in the absence of cholesterol, underlining the need to fully consider multiple lipid species when investigating small transmembrane protein oligomer ion-channel structure and conductance.


Assuntos
Bicamadas Lipídicas , Lipídeos de Membrana , Bicamadas Lipídicas/química , Proteínas de Ligação ao Cálcio/química , Cátions/metabolismo
8.
Sci Rep ; 12(1): 9178, 2022 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-35655073

RESUMO

This study aimed to compare the predictive performance of different modeling methods in developing normal tissue complication probability (NTCP) models for predicting radiation-induced esophagitis (RE) in non-small cell lung cancer (NSCLC) patients receiving proton radiotherapy. The dataset was composed of 328 NSCLC patients receiving passive-scattering proton therapy and 41.6% of the patients experienced ≥ grade 2 RE. Five modeling methods were used to build NTCP models: standard Lyman-Kutcher-Burman (sLKB), generalized LKB (gLKB), multivariable logistic regression using two variable selection procedures-stepwise forward selection (Stepwise-MLR), and least absolute shrinkage and selection operator (LASSO-MLR), and support vector machines (SVM). Predictive performance was internally validated by a bootstrap approach for each modeling method. The overall performance, discriminative ability, and calibration were assessed using the Negelkerke R2, area under the receiver operator curve (AUC), and Hosmer-Lemeshow test, respectively. The LASSO-MLR model showed the best discriminative ability with an AUC value of 0.799 (95% confidence interval (CI): 0.763-0.854), and the best overall performance with a Negelkerke R2 value of 0.332 (95% CI: 0.266-0.486). Both of the optimism-corrected Negelkerke R2 values of the SVM and sLKB models were 0.301. The optimism-corrected AUC of the gLKB model (0.796) was higher than that of the SVM model (0.784). The sLKB model had the smallest optimism in the model variation and discriminative ability. In the context of classification and probability estimation for predicting the NTCP for radiation-induced esophagitis, the MLR model developed with LASSO provided the best predictive results. The simplest LKB modeling had similar or even better predictive performance than the most complex SVM modeling, and it was least likely to overfit the training data. The advanced machine learning approach might have limited applicability in clinical settings with a relatively small amount of data.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Esofagite , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Esofagite/diagnóstico , Esofagite/etiologia , Humanos , Neoplasias Pulmonares/radioterapia , Probabilidade , Prótons
9.
Front Oncol ; 12: 871871, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35547874

RESUMO

As a useful tool, artificial intelligence has surpassed human beings in many fields. Artificial intelligence-based automated radiotherapy planning strategies have been proposed in lots of cancer sites and are the future of treatment planning. Postmastectomy radiotherapy (PMRT) decreases local recurrence probability and improves overall survival, and volumetric modulated arc therapy (VMAT) has gradually become the mainstream technique of radiotherapy. However, there are few customized effective automated treatment planning schemes for postmastectomy VMAT so far. This study investigated an artificial intelligence based automated planning using the MD Anderson Cancer Center AutoPlan (MDAP) system and Pinnacle treatment planning system (TPS), to effectively generate high-quality postmastectomy VMAT plans. In this study, 20 patients treated with PMRT were retrospectively investigated, including 10 left- and 10 right-sided postmastectomy patients. Chest wall and the supraclavicular, subclavicular, and internal mammary regions were delineated as target volume by radiation oncologists, and 50 Gy in 25 fractions was prescribed. Organs at risk including heart, spinal cord, left lung, right lung, and lungs were also contoured. All patients were planned with VMAT using 2 arcs. An optimization objective template was summarized based on the dose of clinical plans and requirements from oncologists. Several treatment planning parameters were investigated using an artificial intelligence algorithm, including collimation angle, jaw collimator mode, gantry spacing resolution (GSR), and number of start optimization times. The treatment planning parameters with the best performance or that were most preferred were applied to the automated treatment planning method. Dosimetric indexes of automated treatment plans (autoplans) and manual clinical plans were compared by the paired t-test. The jaw tracking mode, 2-degree GSR, and 3 rounds of optimization were selected in all the PMRT autoplans. Additionally, the 350- and 10-degree collimation angles were selected in the left- and right-sided PMRT autoplans, respectively. The uniformity index and conformity index of the planning target volume, mean heart dose, spinal cord D0.03cc, mean lung dose, and V5Gy and V20Gy of the lung of autoplans were significantly better compared with the manual clinical plans. An artificial intelligence-based automated treatment planning method for postmastectomy VMAT has been developed to ensure plan quality and improve clinical efficiency.

10.
J Am Chem Soc ; 144(14): 6442-6452, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35363483

RESUMO

The enantioconvergent radical C(sp3)-C(sp2) cross-coupling of alkyl halides with alkenylboronate esters is an appealing tool in the assembly of synthetically valuable enantioenriched alkenes owing to the ready availability, low toxicity, and air/moisture stability of alkenylboronate esters. Here, we report a copper/chiral N,N,N-ligand catalytic system for the enantioconvergent cross-coupling of benzyl/propargyl halides with alkenylboronate esters (>80 examples) with good functional group tolerance. The key to the success is the rational design of hemilabile N,N,N-ligands by mounting steric hindrance at the ortho position of one coordinating quinoline ring. Thus, the newly designed ligand could not only promote the radical cross-coupling process in the tridentate form but also deliver enantiocontrol over highly reactive alkyl radicals in the bidentate form. Facile follow-up transformations highlight its potential utility in the synthesis of various enantioenriched building blocks as well as in the late-stage functionalization for drug discovery.


Assuntos
Cobre , Ésteres , Alcenos , Catálise , Ligantes
11.
Comput Struct Biotechnol J ; 20: 573-582, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35047128

RESUMO

The M protein of the novel coronavirus 2019 (SARS-CoV-2) is the major structural component of the viral envelope and is also the minimum requirement for virus particle budding. M proteins generally exist as dimers. In virus assembly, they are the main driving force for envelope formation through lateral interactions and interactions with other viral structural proteins that play a central role. We built 100 candidate models and finally analyzed the six most convincing structural features of the SARS-CoV-2 M protein dimer based on long-timescale molecular dynamics (MD) simulations, multiple free energy analyses (potential mean force (PMF) and molecular mechanics Poisson-Boltzmann surface area (MMPBSA)) and principal component analysis (PCA) to obtain the most reasonable structure. The dimer stability was found to depend on the Leu-Ile zipper motif and aromatic amino acids in the transmembrane domain (TMD). Furthermore, the C-terminal domain (CTD) effects were relatively small. These results highlight a model in which there is sufficient binding affinity between the TMDs of M proteins to form dimers through the residues at the interface of the three transmembrane helices (TMHs). This study aims to help find more effective inhibitors of SARS-CoV-2 M dimers and to develop vaccines based on structural information.

12.
PLoS One ; 16(4): e0250819, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33914818

RESUMO

The Siwa archaeological culture (ca. 3350 and 2650 cal yr BP) has often been associated with the tribes referenced in textual sources as Qiang and Rong: prized captives commonly sacrificed by the Shang and marauding hordes who toppled the Western Zhou dynasty. In early Chinese writings, food plays a key role in accentuating the 'sino-barbarian' dichotomy believed to have taken root over 3000 years ago, with the Qiang and Rong described as nomadic pastoralists who consumed more meat than grain and knew little of proper dining etiquette. To date, however, little direct archaeological evidence has allowed us to reconstruct the diet and foodways of the groups who occupied the Loess Plateau during this pivotal period. Here we present the results of the first ceramic use-wear study performed on the Siwa ma'an jars from the site of Zhanqi, combined with the molecular and isotopic characterization of lipid residues from foodcrusts, and evidence from experimental cooking. We report molecular data indicating the preparation of meals composed of millet and ruminant dairy among the Siwa community of Zhanqi. Use-wear analysis shows that Zhanqi community members were sophisticated creators of ceramic equipment, the ma'an cooking pot, which allowed them to prepare a wide number of dishes with limited fuel. These findings support recent isotope studies at Zhanqi as well as nuance the centrality of meat in the Siwa period diet.


Assuntos
Cerâmica/química , Utensílios de Alimentação e Culinária/história , Laticínios/análise , Milhetes/genética , Arqueologia , Isótopos de Carbono/análise , Cerâmica/história , China , Alimentos/classificação , Alimentos/história , Cromatografia Gasosa-Espectrometria de Massas , História Antiga , Humanos , Isótopos de Nitrogênio/análise
13.
Angew Chem Int Ed Engl ; 60(4): 2160-2164, 2021 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-33052624

RESUMO

In contrast to the wealth of asymmetric transformations for generating central chirality from alkyl radicals, the enantiocontrol over the allenyl radicals for forging axial chirality represents an uncharted domain. The challenge arises from the unique elongated linear configuration of the allenyl radicals that necessitates the stereo-differentiation of remote motifs away from the radical reaction site. We herein describe a copper-catalyzed asymmetric radical 1,4-carboalkynylation of 1,3-enynes via the coupling of allenyl radicals with terminal alkynes, providing diverse synthetically challenging tetrasubstituted chiral allenes. A chiral N,N,P-ligand is crucial for both the reaction initiation and the enantiocontrol over the highly reactive allenyl radicals. The reaction features a broad substrate scope, covering a variety of (hetero)aryl and alkyl alkynes and 1,3-enynes as well as radical precursors with excellent functional group tolerance.

14.
Angew Chem Int Ed Engl ; 60(1): 380-384, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-32949177

RESUMO

The development of enantioconvergent cross-coupling of racemic alkyl halides directly with heteroarene C(sp2 )-H bonds has been impeded by the use of a base at elevated temperature that leads to racemization. We herein report a copper(I)/cinchona-alkaloid-derived N,N,P-ligand catalytic system that enables oxidative addition with racemic alkyl bromides under mild conditions. Thus, coupling with azole C(sp2 )-H bonds has been achieved in high enantioselectivity, affording a number of potentially useful α-chiral alkylated azoles, such as 1,3,4-oxadiazoles, oxazoles, and benzo[d]oxazoles as well as 1,3,4-triazoles, for drug discovery. Mechanistic experiments indicated facile deprotonation of an azole C(sp2 )-H bond and the involvement of alkyl radical species under the reaction conditions.

15.
Ann Transl Med ; 8(18): 1144, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33240993

RESUMO

BACKGROUND: We aimed to analyze the value of metal clip markers guided and placed by endoscopic ultrasonography (EUS) in the delineation of gross tumor volume (GTV) for thoracic esophageal squamous cell carcinoma. METHODS: From September 2016 to September 2018, patients with thoracic esophageal squamous cell carcinoma in Tianjin Medical University Cancer Institute and Hospital were recruited in the prospective trial, NCT02959385. They underwent titanium clips placement on tumor superior and inferior boundaries under EUS by a single expert endosonographer before radiotherapy computed tomography (CT) simulation. According to the clip markers, the reference GTVs were contoured by one experienced radiation oncologist. With the help of the Eclipse treatment planning system, clip markers on CT were concealed. Afterward, two other radiation oncologists with expertise in esophageal cancer delineated GTVs, defined as conventional GTVs, based on endoscopy and barium radiography findings. The two GTVs were compared and analyzed. Subgroup analysis was conducted in different T stage [early (T1 + T2) vs. advanced (T3 + T4)], focus location (upper vs. middle vs. lower segment), and tumor length (<5 vs. >5 cm) groups. RESULTS: The trial recruited 55 patients with 60 thoracic esophageal cancer foci. A total of 111 titanium clips were guided and implanted by EUS. Before CT simulation, two titanium clips at two foci fell off. After the procedure, no case of intolerable esophageal pain, hemorrhage, or perforation occurred. Compared to reference GTVs', discrepancies of conventional GTVs' superior borders were 0.91±0.82 cm (P<0.001), while differences of inferior borders were 0.74±0.63 cm (P<0.001). On the contrary, conventional GTVs' lengths were not significantly different from reference GTVs' with discrepancies 0.08±1.30 cm (P=0.64). Regardless of T stage, tumor location, and tumor length, conventional GTVs' superior and inferior borders were significantly different from reference GTVs', while GTVs' lengths differed insignificantly. CONCLUSIONS: This study confirmed that EUS-placed titanium clips could correct contouring of GTVs in thoracic esophageal cancer in different T stages, tumor locations, and lengths.

16.
J Am Chem Soc ; 142(46): 19652-19659, 2020 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-33146993

RESUMO

A copper-catalyzed enantioconvergent Suzuki-Miyaura C(sp3)-C(sp2) cross-coupling of various racemic alkyl halides with organoboronate esters has been established in high enantioselectivity. Critical to the success is the use of a chiral cinchona alkaloid-derived N,N,P-ligand for not only enhancing the reducing capability of copper catalyst to favor a stereoablative radical pathway over a stereospecific SN2-type process but also providing an ideal chiral environment to achieve the challenging enantiocontrol over the highly reactive radical species. The reaction has a broad scope with respect to both coupling partners, covering aryl- and heteroarylboronate esters, as well as benzyl-, heterobenzyl-, and propargyl bromides and chlorides with good functional group compatibility. Thus, it provides expedient access toward a range of useful enantioenriched skeletons featuring chiral tertiary benzylic stereocenters.

17.
Radiother Oncol ; 146: 200-204, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32220701

RESUMO

PURPOSE: To develop and test an Lyman-Kutcher-Burman (LKB) normal tissue complication probability (NTCP) model to predict radiation-induced esophagitis (RE) in non-small cell lung cancer (NSCLC) patients receiving passive-scattering proton therapy (PSPT). MATERIAL AND METHODS: We retrospectively reviewed 328 NSCLC patients receiving PSPT at our institution. Esophagitis severity was graded by physicians according to the Common Toxicity Criteria for Adverse Events version 3.0, and the primary endpoint was grade ≥2 RE within 6 months from the first treatment. LKB model parameters (n, m, and TD50) were determined using maximum likelihood estimation. Overall performance of the model was quantified by Nagelkerke's R2 and the scaled Brier score. Discriminative ability was evaluated using the area under the receiver operating curve (AUC), and calibration was assessed with the Hosmer-Lemeshow goodness-of-fit test. Bootstrap internal validation was performed to assess the model uncertainty and generalizability. RESULTS: Grade 2-3 RE was observed in 136 (41.5%) patients, and no grade 4-5 RE was reported. The optimal LKB parameters were: n = 0.24, m = 0.51, and TD50 = 44.83 Gy (relative biological effectiveness). The optimism-corrected AUC was 0.783, and the Hosmer-Lemeshow test showed significant agreement between predicted and observed morbidity. Bootstrap validation verified that the model was robust to similar future populations. CONCLUSION: Our LKB NTCP model to predict grade ≥2 RE in NSCLC patients who received PSPT showed good predictive performance and robustness to similar future populations, and a smaller volume effect than the previously observed in photon-treated populations. External validation of the model is warranted.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Esofagite , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Esofagite/etiologia , Humanos , Neoplasias Pulmonares/radioterapia , Probabilidade , Prótons , Dosagem Radioterapêutica , Estudos Retrospectivos
18.
Nat Chem ; 11(12): 1158-1166, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31636393

RESUMO

Continued development of the Sonogashira coupling has made it a well established and versatile reaction for the straightforward formation of C-C bonds, forging the carbon skeletons of broadly useful functionalized molecules. However, asymmetric Sonogashira coupling, particularly for C(sp3)-C(sp) bond formation, has remained largely unexplored. Here we demonstrate a general stereoconvergent Sonogashira C(sp3)-C(sp) cross-coupling of a broad range of terminal alkynes and racemic alkyl halides (>120 examples) that are enabled by copper-catalysed radical-involved alkynylation using a chiral cinchona alkaloid-based P,N-ligand. Industrially relevant acetylene and propyne are successfully incorporated, laying the foundation for scalable and economic synthetic applications. The potential utility of this method is demonstrated in the facile synthesis of stereoenriched bioactive or functional molecule derivatives, medicinal compounds and natural products that feature a range of chiral C(sp3)-C(sp/sp2/sp3) bonds. This work emphasizes the importance of radical species for developing enantioconvergent transformations.

19.
J Cancer ; 10(21): 5057-5064, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31602257

RESUMO

Backgrounds: With the excellent local control in T1 to T3 nasopharyngeal carcinoma (NPC) treated with intensity modulated radiotherapy (IMRT), the importance of toxicities is increasingly being recognised. This retrospective propensity score analysis sought to assess whether moderate dose reduction compromised long-term outcome compared with standard dose in T1-3 NPCs. Materials and Methods: A total of 266 patients (67 female, 199 male) with a median age of 50 years between June 2011 and June 2015 were analysed. All were treated with IMRT, with or without systemic chemotherapy. The prescription radiation dose to gross tumor is 70Gy/2.12Gy/33F in our institution. Results: With a median follow-up time of 50 months, the 5-year loco-regional failure-free survival (LRFS) and overall survival (OS) were 93.5% and 81.8%, respectively. 32 patients received radiation dose less than prescription dose, with a median dose of 63.6Gy (53-67Gy). Another 234 patients received exactly the prescription dose of 70Gy. Propensity scores were computed (32 patients treated with de-escalated dose and 64 patients with standard dose), there was no significant difference in 5-year LRFS and 5-year OS between the two groups (92.5% and 91.7% with standard dose; 82.1% and 85.7% with de-escalation dose; p=0.863 for LRFS and 0.869 for OS). No independent prognostic factor was associated with loco-regional failure in univariate analysis. Conclusions: T1-3 nasopharyngeal carcinoma presenting with superior locoregional control, a moderately reduced dose (about 10%) delivered with IMRT resulted in comparable prognosis to those with prescription dose of 70Gy.

20.
Onco Targets Ther ; 12: 1259-1268, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30863093

RESUMO

PURPOSE: To determine the efficacy and late toxicities of moderate (2.5-4 Gy) hypofractionated radiotherapy (H-RT) in localized prostate cancer, a meta-analysis of published randomized clinical trials comparing moderate H-RT with conventional fractionated RT (C-RT) was performed. MATERIALS AND METHODS: Systematic search on published randomized clinical trials in English according to Cochrane review guidelines in databases of Pubmed, Embase, Cochrane, web of science, and Wiley Online Library was carried out. Outcomes of interests were biochemical and clinical disease failure (BCDF), biochemical failure (BF), overall survival (OS), and late toxicities. RESULTS: Seven of the 365 studies fulfilled inclusion criteria with 8,156 participants. Compared with C-RT, moderate H-RT showed a lower BF rate (risk ratio [RR] =0.80, 95% CI: 0.68-0.95, P=0.009), while did not improve OS (RR =0.68, 95% CI: 0.78-1.02, P=0.10). There was no significant difference in BCDF rates between H-RT and C-RT (RR =0.92, 95% CI: 0.82-1.02, P=0.12). The H-RT was deeply grouped into dose-escalated H-RT (with a higher biologically effective dose [BED1.5] than C-RT) and no dose-escalated H-RT; dose-escalated H-RT significantly decreased BCDF rate compared with C-RT (RR =0.84, 95% CI: 0.73-0.96, P=0.01). Regarding late toxicities, there is no significant difference in late gastrointestinal (GI; RR =0.97, 95% CI: 0.71-1.33, P=0.85) and genitourinary (GU) toxicities (RR =1.04, 95% CI: 0.87-1.24, P=0.69). When subgrouped into dose-escalated H-RT (with a higher BED5 compared with C-RT) and no dose-escalated H-RT, dose-escalated H-RT increased GI toxicity (RR =1.62, 95% CI: 1.26-2.09, P=0.0002) and GU toxicity (RR =1.28, 95% CI: 1.05-1.55, P=0.01), while no dose-escalated H-RT significantly lowered GI toxicity (RR =0.81, 95% CI: 0.70-0.94, P=0.005) and placed no influence on GU toxicity (RR =1.02, 95% CI: 0.88-1.20, P=0.77). CONCLUSION: This meta-analysis provides reliable evidence that moderate H-RT decreases BF rate, while does not improve OS. Compared with C-RT, H-RT with an increase in BED1.5 improved BCDF rates significantly, and accordingly, an increase in BED5 will result in elevated late GI and GU toxicities.

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